1. The GAINS optimization approach – Basic background information Fabian Wagner International Institute for Applied Systems Analysis (IIASA) IIASA workshop on The use of the GAINS model for the revision of the Gothenburg protocol Laxenburg 20 June 2011

2. Overview Why we use optimization tools How we use optimization tools Frequently Asked Questions

3. SO 2 measures NO x measures NH 3 measures VOC measures PM measures Energy Industry Transport Agriculture Other (e.g Waste) Costs SO 2 NO x PM NH 3 VOC Why we use optimization tools With the GAINS online model we SIMULATE future emissions, air pollution control costs S deposition NO y deposition O 3 production Secondary aerosols Primary PM concentration NH 4 + deposition PM Exposure Humans O 3 Exposure Humans Exceedance CL nitrogen Exceedance CL acidification Env. Impacts Targets and environmental impacts

4. Why we use optimization tools Because we are seeking to identify cost-effective portfolios of technologies that reach a given set of environmental targets at the lowest possible cost. And we need to take into account: Future emissions are different in different countries (and for different pollutants) Potentials and costs for control technologies are different Different pollutants have different environmental effects Optimization is a systematic procedure to address this problem

5. SO 2 measures NO x measures NH 3 measures VOC measures PM measures Energy Industry Transport Agriculture Other (e.g Waste) Costs SO 2 NO x PM NH 3 VOC Target setting: effects-based approach S deposition NO y deposition O 3 production Secondary aerosols Primary PM concentration NH 4 + deposition PM Exposure Humans O 3 Exposure Humans Exceedance CL nitrogen Exceedance CL acidification Env. Impacts Targets

6. Target setting: the feasible range (‘gap’) Emissions Impacts

7. Target setting: the feasible range (‘gap’) MFR = ‘maximum feasible reduction’ = lowest feasible level Emissions Impacts ‘Gap’

8. Target setting: domestic and transboundary implications In order to calculate the ‘gap’ in one country we need to calculate the baseline emissions and the MFR emissions in ALL countries.

9. Setting comparable targets in different countries: The ‘equal environmental progress’ (‘gap closure’) concept 100% of gap 25% of gap 50% of gap 75% of gap

10. Setting comparable targets in different countries: The ‘equal environmental progress’ (‘gap closure’) concept Country ACountry B

11. Gap closure procedure For a given environmental impact indicator the same percentage is applied in each country

12. Four impact indicators considered Years of life lost (YOLL) – [PM2.5, SO2, NOx, NH3] Acidification – [SO2, NOx, NH3] Eutrophication [NOx, NH3] Health-related Ozone – SOMO35 [NOx, VOC]

13. Formulating the optimization Minimize European-wide air pollution control cost, such that: –Environmental targets are met in each country and overall But also take into account: –Technical limitations on new technologies –Existing technology has a lifetime –Road vehicle emission control measures remain as in the baseline

14. Frequently Asked Questions (FAQ) Why does my country have to reduce more than my neighbour? –Maybe your country has a higher environmental impact and hence your reductions result in higher benefits –Maybe emission reductions in your country are relatively less expensive Why does my country have to reduce more of X (e.g. SO2) than of Y (e.g. NH3)? –Maybe it is less expensive to reduce more of X –Maybe it is just more cost-effective to reduce more of X –Maybe due to atmospheric dispersion reducing X is just more effective

15. Conclusions We use optimization because –We are looking for cost-effective solutions –We are setting targets on effects, but would like to find out a set of upstream technology portfolios (and this is a complex task!) The optimization only utilizes: –Input data from the GAINS database (act. projections, tech. costs and emission factors; atmospheric dispersion; critical loads) –Environmental targets that are formulated as ‘equal environmental progress’ (gap closure) Results can always be explained by cost-effectiveness, even though sometimes they initially appear unintuitive